Be carefull the following days with trunk, as there can still be some unstability. In rev 20658 I have converted:

1/ no more cmp and __cmp__, so also not in sort and sorted
2/ bsddb needs a bytestring key, so b'string', which is str of python 2. Fortunately, b'string' works in python 2
3/ gtk in python 3 needs just str (so unicode), not utf-8 anymore

Gramps starts to work with python3, at least editors, and some views. Only test with real test data, as low bsddb corruption errors still happen!!

Most remaining things I think will be unicode <--> bytestring <--> utf-8 issues, but if those go into the database, it could be problematic!